1. Field of the Invention
The present invention relates generally to an improved lighting fixture and more specifically to an improved lighting fixture having a plurality of independently adjustable light emitting diodes or LEDs to provide illumination to a plurality of lighting areas.
2. Description of the Related Art
Many lighting fixtures utilize light-emitting diodes, or LEDs. For example, U.S. Patent Pub. No. 2002/1036009A1 to Yoneda, teaches a pair of light emitting members where each member includes a plurality of LEDs disposed to form a flare shape. Cylindrical lenses are disposed where they capture light emitted from the LED members and concentrate it onto a given surface. Thus a specific area of a subject can be illuminated for inspection by adjusting the pitch of the lenses at the time of bonding them to the lens support plate to vary the light concentrated area.
U.S. Patent Pub. No. 2002/0114155A1 to Katogi et al., teaches an illumination unit comprised of a plurality of LEDs positioned on a base plate and encircled by a clear glass tube. The plurality of LEDs is placed on a single long rectangular base plate. U.S. Pat. No. 5,410,453 issued to Ruskouski, teaches a lighting device for illuminating an exit sign. The device is comprised of a plurality of light directing apertures on one side with a plurality of LEDs recessed into the apertures. The LEDs are mounted on circuit mounting means and the light from the LEDs is thence directed towards an exit sign.
With the advent of high wattage LEDs, increased efficiency, and decreased heat dissipation, it is desirable to devise a luminaire utilizing these high efficiency light sources. However, even the most powerful LEDs feasible to employ for commercial lighting use currently have only a 5-Watt maximum output, yielding approximately 150 lumens. Such an LED has an integral lens, yielding a well-defined beam pattern. Since each LED comprises a light-emitting member having a specified width, concentrating light requires a lens having a larger diameter, which is often very expensive. While the use of redesigned and modified lenses for concentrating light emitted from the LEDs is feasible, it is economically preferable to utilize existing lenses.
However, the aforementioned prior art luminaires do not provide a lighting system capable of a high degree of adjustment for illumination of a wide variety of lighting zones. A plurality of LEDs with lenses for concentrating light in a particular area may be used if desired, but the use of such lenses is expensive. LEDs which may be individually adjustable to concentrate and focus the light provided by a luminaire are desired.